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//
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//! Helper function and struct to find input columns for an Expr;

use datafusion::logical_expr::expr::Expr as DfLogicalExpr;

pub fn find_columns_by_expr(expr: &DfLogicalExpr) -> Vec<String> {
    expr.to_columns()
        .unwrap()
        .into_iter()
        .map(|col| col.name)
        .collect()
}
